Rich: What you are saying is extremely interesting. As a follow on question
and as an example; irrational transcendental numbers, like pi and e, cannot be
described 100% accurately in our standard base 10 number system because they go
on forever and have no end. So the computer system must first convert this type
of a number to a binary number, processes it and then convert it back to base
10 for our use. Somewhere along the process, the computer is going to have to
decide just where it will round off or truncate the digits within the number
and this is where the error is introduced? Is this the type of error to which
you allude? - 73's- Corn -k4own.
>>> "Richard B Drake" <rich@w3zj.com> 05/17/01 01:05PM >>>
Even the worlds largest super computers can not to floating point
arithmetic 100% accurately. This is because it is physically
impossible to represent fractional values 100% accurately in
binary. The more bits that are used in the process, the more
accurate it becomes but complex calculations have to be planned
out very carefully to minimize the error and in the end there is
always some rounding required. When you are talking about needing
accuracy in area of fractional parts per million (10 Hz out of
30MHz) a 32 or even 64 bit floating point processor is in over its
head.
----
73, Rich - W3ZJ
> -----Original Message-----
> From: owner-tentec@contesting.com
> [mailto:owner-tentec@contesting.com]On
> Behalf Of Carl Hyde
> Sent: Thursday, May 17, 2001 10:59 AM
> To: W B Reese; tentec@contesting.com
> Subject: Re: [TenTec] Re: TenTec Amateur Radio Digest V4 #145
>
>
>
> The drifting Mark is seeing in Digipan is due more to
> the software and the
> computers Real Time Clock that to the Omni V's drift.
> Remember PC Processors
> don't do floating point math very well.
>
> TT sets the offset to 600 Hz so just tune 600 away from
> the point where the
> other guys cw tone dissapears.
>
> Hell we've been sending and receiving CW with drifty
> old tube radios with no
> crystals since ham radio began. How accurate does it
> have to be? Not as
> accurate as it is.
>
>
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